Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO392.TXT

Internet Message Format | 1993-07-13 | 30KB

Date: Wed, 31 Mar 93 05:00:10
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #392
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 31 Mar 93       Volume 16 : Issue 392

Today's Topics:
 Acceptable metric conversions (was Re: Pioneer Venus Last Findings)
    Aluminum, James Burke, and The Lost Secrets of the Ancients...
                        Atlas rocket question
                   Automated Galaxy Classification
                    Breathing 100 atm. of anything
                Gemini 8 (was Re: Artificial Gravity)
                            GIF's of DC-X
                     Magellan Venus Maps (2 msgs)
           Modulated Directed Tachyons for Commo? (2 msgs)
                     SSF Redesign (and Gimballs)
                 SSTO: A Spaceship for the rest of us
                   STS-1 DISASTER/COVERUP (2 msgs)
           the call to space (was Re: Clueless Szaboisms )
                            Time Machine!?
                 US Satellite Crashing on Brisbane??
                    Venus Atmosphere Paper (long)
          Wanted: Satellite tracking software for unix & VMS
                         Why is Venus so bad?

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----------------------------------------------------------------------

Date: Tue, 30 Mar 93 09:07:36 PST
From: "UTADNX::UTDSSA::GREER"@utspan.span.nasa.gov
Subject: Acceptable metric conversions (was Re: Pioneer Venus Last Findings)

In Space Digest V16 #389,
Mark Brader <[e-mail]> writes:

>> > ... between 25 and 75 feet deep (762 and 2286 centimeters)....
>> > Maybe we should send the PR crew back to Introductory Physics and teach
>> > them about significant digits ...
>>
>> Now for your
>> homework, imagine you are the boss of Public Affairs for a NASA
>> center.  Write guidelines, in 300 words or less, which will guarantee
>> that your employees will always produce acceptable English-to-metric
>> and metric-to-English conversion figures in their press releases.
>
>May I try?
>
>"Henceforth, all press releases are to be proofread by a technical
>writer or writers competent in the relevant area."
>
>I doubt they'd need to put someone on it full-time.

Or just do it with software!  I'm sure these press releases are written on
some kind of computers, and it's obvious that they use some sort of
calculator or calculator software to do the conversions.  Make a special
software calculator that converts and rounds automatically, and require
people to use that when they make press releases.

_____________
Dale M. Greer, whose opinions are not to be confused with those of the
Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER
"Let machines multiply, doing the work of many,
                     But let the people have no use for them." - Lao Tzu

------------------------------

Date: Tue, 30 Mar 93 14:53:40 GMT
From: Dave Jones <[e-mail]>
Subject: Aluminum, James Burke, and The Lost Secrets of the Ancients...
Newsgroups: sci.space

AJ Madison ([e-mail]) wrote:
>
> You folks have been talking about this for a couple of weeks now, and
> you've managed to mention gold occasionally, making me think that
> someone would eventually realize where some of these large chunks of Al
> could have orginated so very long ago...
>
> Yes, that's right, nuggets of almost pure metal.  Collect enough
> nuggets, melt them down and construct the object of your choice.  No
> massive amounts of electricity required, no bizarre loss in technology,
> no early leap in science which is later lost.
>

I'm afraid your chemistry is seriously off here.  Finding metals in 'native'
form, i.e. as the pure metal ore rather than an oxide, sulphide etc, is a
function of the readiness with which the metal converts to an ionic form.
(This is more usually described as the redox potential).  Aluminum is one of
the more reactive metals in this respect, certainly more reactive than iron,
which is never found in native form.  The only thing that prevents Al
corroding faster than iron is the protective layer of oxide that forms on
the surface.  There is no way metallic Aluminum would survive for millions
of years, and no known geological way of creating it.  If you find any in the
ground, it must have been refined from alumina.

Needless to say, Gold et al do not readily convert to ions and _do_ persist
on geological timescales.

--
||Nothing can prepare you for the revelation   ||
||that your favorite movie director is a dweeb.||
||---------------------------------------------||
||Dave Jones ([e-mail])--------||

------------------------------

Date: 20 Mar 93 11:11:26 GMT
From: Michael Richards <[e-mail]>
Subject: Atlas rocket question
Newsgroups: sci.space

Dear All.

    Nice easy one here for all the experts out there, but its baffled
me for quite some time....

    Looking at footage of the Mercury programme launches, the Atlas
rockets (I think?) all seem to have a feature that I've never seen in any
other rocket.  Just above the base of the first stage seem to be at least one,
or possibly more small engines that fire at an angle to the main engines.

    What were these engines? Some kind of stabiliser?

                An inquiring mind must know!

                    Thanks in advance.

                        Mike.
--
* Mike Richards is always willing to spend his time discussing arcane topics  *
* and would much prefer to get mail from obscure places at strange hours than *
* work. So go on!!!! What are you waiting for? He's expecting your mail at    *
* the following address. ---------> [e-mail] <--------- Call now !!!    *

------------------------------

Date: Tue, 30 Mar 1993 03:25:12 GMT
From: yellooW ynohtnA <[e-mail]>
Subject: Automated Galaxy Classification
Newsgroups: sci.space

Hello there! :)

    I would like to know if anyone out there has used (or knows of
    anyone who has applied) neural networks for galaxy classification.
    If you can help me in this could you please email me at:

                 [e-mail]

    Any help would be greatly appreciated.

                 Thanks in advance.

                       Anthony Woolley.
--
            Anthony Woolley    [e-mail]
           This message was proudly brought to you on behalf of
                      Leisure World International
          "Welcome back to reality!" (Back to Reality, Red Dwarf)

------------------------------

Date: Tue, 30 Mar 1993 13:28:19 GMT
From: Thomas Clarke <[e-mail]>
Subject: Breathing 100 atm. of anything
Newsgroups: sci.space

In article <[e-mail]> [e-mail]
(Francois Yergeau) writes:
> In article <[e-mail]> [e-mail] (Doug Loss)
writes:
> >It seems to me that the major problem, everything else assumed to be OK,
> >is that at 100 atm. the viscosity of _any_ gasses is such that a human
> >diaphragm will fatigue and cease functioning, causing suffocation
> >regardless of partial pressures, etc.
>
>
> The rubber bible says that for air, viscosity is independant of
> pressure up to 40 atm (no data past that).  They also give a formula
> for the volume of a viscous fluid escaping from a tube of radius r and
> length l:
>
>     v = (Pi.p.r^4) / (8.l.eta),
>
> where eta is viscosity and p is the pressure differential.
I think there are two viscosities.  The kinematic viscosity has the
density factored out and would be independent of pressure.  This is
the one that usuaally appears in Navier stokes equations (symbol mu
usually ?).
The ordinary viscosity is force/unit-area/velocity-gradient and would
vary with density.  Since density = mass/volume, dividing this (eta ?)
by density gives length-squared/time, independent of mass.  The ordinary
viscosity is used in engineering calculations.  Surprised the rubber
bible isn't more careful about this.
--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
[phone], FAX: [phone], [e-mail]

------------------------------

Date: 30 Mar 93 07:50:30 EST
From: Chris Jones <[e-mail]>
Subject: Gemini 8 (was Re: Artificial Gravity)
Newsgroups: sci.space

In article <[e-mail]>, davem@ee (Dave Michelson) writes:
>That's interesting.  The only comment that I had ever read was that "a
>thruster had stuck open".  No mention as to why... or how they closed
>it.  I was under the vague impression that a short circuit was the
>culprit and that they had to shut down the entire OAMS system in the
>adapter section and fire up the re-entry thrusters in the re-entry section
>to stabilize the spacecraft.

The post-mortem did blame the problem on a short-circuit.  The problem started
with the two spacecraft (Agena and Gemini) docked.  The combination started
twisting, with thrusters on both spacecraft firing.  Armstrong figured the
Agena had malfunctioned and undocked to back away.  Somewhat to their surprise,
the Agena became rock-solid, while the Gemini's spin rate (it was a roll
thruster stuck on, as I recall) continued to increase, reaching 60 RPM or so.
There was a movie camera mounted in Dave Scott's window shooting during this
time, but all you can see as the rate increases is lots of orange and white
blotches as the sun whizzes by.

>The mission was terminated precisely because Armstrong and Scott had used the
>re-entry thrusters to stabilize the spacecraft.  Could they have solved
>the problem simply by resetting the onboard computer and then gone on with the
>mission?

I'd bet not.  Since they knew that by using the reentry system they were
forcing an end to the mission, I expect they tried (or at least considered) all
the plausible alternatives before taking that step.  Mike Collins has written
that Armstrong must have loved making decisions because he always seemed to
prolong the process -- he wasn't surprised that Eagle had less than 30 seconds
of fuel left when Armstrong set it down on the moon.  (What was it with
Armstrong, anyway?  He also had to eject from an LLRV when rehearsing a lunar
landing.)

The Gemini 8 Agena was boosted into a higher orbit.  Its batteries died, but
Gemini 10, piloted by John Young and Mike Collins, was able to rendezvous with
it, and Collins performed an EVA over to it to retrieve a micrometeorite
detection package that had been intended to be returned on one of Scott's
planned EVAs.
--
Chris Jones    [e-mail]

------------------------------

Date: Tue, 30 Mar 93 11:24:33 EST
From: [e-mail]
Subject: GIF's of DC-X

Didn't I see that someone had loaded some GIF's of DC-X somewhere?

Kevin Cain
[e-mail]

------------------------------

Date: Tue, 30 Mar 1993 14:26:43 GMT
From: "Thomas E. Smith" <[e-mail]>
Subject: Magellan Venus Maps
Newsgroups: sci.space

Are there any venus altitude maps in U.S. geological format? I think it's
referred to as .DEM format. I have an Amiga, with VistaPro, which can take
these altitude files and render pictures of the landscapes with all kinds
of user definable settings. And it used straight U.S. geological format.
A source of any other .DEM maps would be much appreciated.


------------------------------------------------------------------------------
| Living on Earth may be expensive,|Tom E. Smith               | ._________  |
| but it includes an annual free   |[e-mail]| |= (0_, \ \ |
| trip around the Sun.             |                           | |= |0 ` / | |
|--------------------------------------------------------------| |---u----/  |
| And no, I don't speak for my company or any other company.   |             |
------------------------------------------------------------------------------

------------------------------

Date: Tue, 30 Mar 1993 14:30:32 GMT
From: "Thomas E. Smith" <[e-mail]>
Subject: Magellan Venus Maps
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Are there any venus altitude maps in U.S. geological format? I think it's
referred to as .DEM format. I have an Amiga, with VistaPro, which can take
these altitude files and render pictures of the landscapes with all kinds
of user definable settings. And it used straight U.S. geological format.
A source of any other .DEM maps would be much appreciated.


------------------------------------------------------------------------------
| Living on Earth may be expensive,|Tom E. Smith               | ._________  |
| but it includes an annual free   |[e-mail]| |= (0_, \ \ |
| trip around the Sun.             |                           | |= |0 ` / | |
|--------------------------------------------------------------| |---u----/  |
| And no, I don't speak for my company or any other company.   |             |
------------------------------------------------------------------------------

------------------------------

Date: Tue, 30 Mar 1993 13:21:48 GMT
From: "Simon E. Booth" <[e-mail]>
Subject: Modulated Directed Tachyons for Commo?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Josh Hopkins) writes:
>[e-mail] (Simon E. Booth) writes:
>
>>And then of course there are the particles discovered during the
>>mid 1970's-
>
>>TACKY-ONS!!
>>:-)
>
>Recent research has indicated that the scientists who discovered the Tacky-ons
>were probably incorrect.  In actual fact, they stumbled upon the fundamental
>particle of stupidity - the moron.
Simon

------------------------------

Date: Tue, 30 Mar 93 15:00:55 GMT
From: Dave Jones <[e-mail]>
Subject: Modulated Directed Tachyons for Commo?
Newsgroups: sci.space

Ray Swartz (Oh, that guy again) ([e-mail]) wrote:
> In article <[e-mail]>, [e-mail] (Simon E. Booth) writes:
> >
> >Darn- and I was hoping they could develop the tachyon bomb- the bomb
> >that detonates before it was dropped....
>
>
>     Actually, I've always liked the idea of a neutrino bomb.  It detonates
> over a target city...
>
>         ... and nobody notices it.
>

Check out the hilarious description of the neutrino bomb quoted in one of
Martin Gardner's books (mid-60s, title forgotten but something to do with
mirror worlds and parity).  Anyway, it involves new particles called the
'fiction' (strangeness 0) and the 'truthiton' (strangeness 1, so truth is
stranger than....) The bomb materials vanish in an instant, leaving a vacuum
into which the air rushes with a loud bang, informing all those around that
they have been had.

--
||Nothing can prepare you for the revelation   ||
||that your favorite movie director is a dweeb.||
||---------------------------------------------||
||Dave Jones ([e-mail])--------||

------------------------------

Date: 29 Mar 93  22:31:24
From: [e-mail]
Subject: SSF Redesign (and Gimballs)
Newsgroups: sci.space

Pat ([e-mail]) wrote:
:     PS DOes anyone have a real solid justification for
: the Alpha gimbbels as opposed to  going solar inertial?
: and placing any earth sensors into a swing boom?

There are several reasons for this --
   First of all, you'll still need gimbals on the solar arrays to
handle the seasonal variation in "beta angle" (angle to the sun).
On SSF these are the beta gimbals.  Without them, you can lose up to
about 30% of your solar power (depending upon season).  Beta
orientation can be done with a combination of Control Moment Gyros
forces and Reaction Control System firings, but those typically take
more fuel than carrying up a small 1-axis gimbal system.
   It should also be noted Alpha gimbals are pretty straight forward
designs -- they rotate once an orbit (ever 90 minutes) in single
direction around a single axis.  To put earth sensors on a platform
to stare at the earth requires a 2 axis "scan platform" which has to
be pretty good quality to get good data (precision and jitter less
than 1 pixel).  While scan platforms are pretty well known
technology, they are not simple. (Note: in Gravity Gradient or Arrow
Mode you'll still have to turn a sensor in 2 axis, but you only need
to track in 1 -- down the orbital track.  In solar pointing, you
have to track in two axes.)
   Secondly, if you keep the Beta angles and drop the Alpha gimbals
to go solar inertial (which should more properly be called "solar
pointing", since there are _very_ few stable configurations which
are really solar inertial) you still have to do some CMG torque or
RCS maneuvering.  This is since gravity gradient forces and
aerodynamic forces are trying to turn the vehicle away from solar
pointing attitude. You can play some games in some configurations
between gravity gradient torques, CMG control algorithms to prevent
saturation of your CMGs, and RCS usage methods to reduce the RCS
propellant burned to maintain solar pointing attitude, but you will
have to maneuver to stay in solar pointing attitude.
   The best configurations for minimal propellant usage are gravity
gradient or "arrow mode" to minimize the torques between Center of
gravity and center of pressure, plus proper placement of Control
Moment Gyros (CMGs) and RCS systems. (yes, there are aerodynamic
forces to be considered).
   [Explanation of jargon: "Gravity Gradient configuration" -- the
vehicle/station is aligned perpendicular to the surface of the
Earth, to minimize the torques from Gravity gradient forces.  These
Gravity gradient forces will continue to try to push the spacecraft
into this attitude as it continues around the orbit -- so the
minimal GG torque is when the spacecraft is in a slow pitch rotation
once per orbit to minimize GG torques.  However, aerodynamic forces
may become significant since the station/vehicle is presenting a
long axis to produce aerodynamic drag from.
   "Arrow mode" -- the vehicle/station is in flight like an arrow
with its long axis aligned along the orbital path  -- "along the
velocity vector". Gravity gradient torques are minimized, since
there is little perpendicular excursions from the orbital path, and
aerodynamic forces are minimized as there is little frontal area
exposed.  You have to again pitch rotate once per orbit to maintain
this mode.]
   Lastly, and most importantly, solar points loses most of your
microgravity environment.  For an analytical rule of thumb at about
250 nmi, the 1e-6 gravity contour (1 uG) traces out an ellipse
perpendicular to the velocity vector of major radius 27.5 feet and
minor radius 8.8 feet, centered about the CG of the space
station/satellite/vehicle.   Along the velocity vector, it continues
for about 100 feet ahead or behind the body in orbit.   To maintain
       _____----------_____         ^
    _ /                    \_       |
  <_                         _>   16.6'    (Looking down along
     \                      /       |       the orbital path)
       -----_________------         v
 <------------ 55' ----------->
the maximum volume of experiments within the 1 uG boundary,  it is
obvious you want to align your modules along the orbital path (in
"arrow mode").  Note also, two 15' diameter modules pretty much fit
into this contour, meaning that SSF can maintain virtually all of
the modules in less than 1uG.
   If you fly in solar pointing mode, you are continually rotating
around your center of mass in two axes (compared to arrow mode) to
maintain solar pointing.  This reduces the available 1 uG zone into
a sphere of about 16.6' diameter. For something like SSF, this
reduces the microgravity preferred zone from 90+% of 4 modules down
to a portion of 1 module.  Outside, you have periodic gravity
fluctuations as you tumble through the microgravity contours.
   And if you bias all of your solar arrays onto one side of the SSF
like the Boeing "FastLab" proposed in the SSF redesign to the Shea
Committee, then you can offset your C.G from the center of a module,
and reduce your available 1uG zone to even a smaller volume.
 ------------------------------------------------------------------
 Wales Larrison                           Space Technology Investor

--- Maximus 2.01wb

------------------------------

Date: 26 Mar 93  16:36:19
From: [e-mail]
Subject: SSTO: A Spaceship for the rest of us
Newsgroups: sci.space

In a message of <Mar 22 08:25>, Dr. Norman J. LaFave
<[e-mail]> writes:

 >Let me take you on a virtual trip.... See the Vehicle
 >Assembly building? That huge structure with massive cranes needed
 >to build the shuttle stack for launch? Not needed for DC (no stack
 >to assemble (and no potential assembly accidents) ).

I was just at MD yesterday being introduced to the DC-X, the FOCC, etc. [For
manned space fans, yes, Pete Conrad was there.]

My understanding is that DC-1 would need a crane or similar apparatus for
swapping out payload modules.

 >See the
 >"crawler" used to roll the shuttle stack out to the pad (the largest
 >land transport on earth)? Yes, the one that uses thousands of gallons of
 >fuel to make the trip out and back. Not needed for DC (can land near
 >where it launches).

My understanding is that the DC series will land on extendable gear but
would launch from a platform while resting on the hardpoints.  The hardpoints
contain the refueling ports.  The gear would be retracted for launch.
Some kind of transporter is needed to pick the vehicle up from where it landed
and take it to the launch platform.

BTW, what was described to me was not "airliner type turnaround" but military
aircraft turnaround types.  There is a difference in non-combat situations.

 > Let's look in the orbiter maintenance buildings....
 >See the turbopumps being torn down for inspection after every flight?
 >That is because the main engines red line during launch. Not the case
 >with the DC design because it never red lines its engines.

You are going to need a similar facility, though, for periodic maintenance.
It isn't supposed to be for every flight but it will be needed.

--- Mark Perew  [e-mail]
--- Mark's Information Repository and Funtime Emporium (1:103/208.201)


--- Squish v1.00

------------------------------

Date: Tue, 30 Mar 1993 14:04:03 GMT
From: Matthew Kaiser <[e-mail]>
Subject: STS-1 DISASTER/COVERUP
Newsgroups: sci.space

ah.. sys adm, sir!

could you please can this "Dr." guy

he's wasting valuable diskspace and
his gases are aggravating the greenhouse effect!!

------------------------------

Date: Tue, 30 Mar 1993 14:28:32 GMT
From: Eric H Seale <[e-mail]>
Subject: STS-1 DISASTER/COVERUP
Newsgroups: sci.space

How do we get this bone-head turned off so that we don't waste so d**n
much bandwidth on "Dr. Peter Beter" and his drivel?

Eric

------------------------------

Date: 29 Mar 93 08:34:33 GMT
From: William Reiken <[e-mail]>
Subject: the call to space (was Re: Clueless Szaboisms )
Newsgroups: sci.space

In article <1p5rar$[e-mail]>, [e-mail] (Pat) writes:
>
> They seriously don't have the room for a mistake.
>

    Most of the mistakes that happened in the US will not happen in
Japan. Why?  Because we already made them.  The Japanese train on US made
nuclear training equipment.  Some of the best in the World.

>
> Also, given that japan has no indigenous sources of radioactives,
> what is the economic difference for japan to import oil,  versus
> radioactives,  of which only a few countries produce.  I believe only
> the US,  France and The soviets produce nuclear fuels.  Maybe india
> does on a small scale.
>
    Shipments of nuclear fuel have already arrived from France and more
are expected.  Also, the Japanese have built (or are building) breeder
reactors.  Not to mention that the Japanese manufacture most of the worlds
most advanced nuclear proccessing equipment.  And of course as already pointed
out by someone else they don't have the Crazed lawyers that America has.  Any
opposition to building a plant is taken care of.  I already wrote something
about how that is handled.

    Unlike America, they don't do things half-ass.


                            Will...

------------------------------

Date: Tue, 30 Mar 1993 07:21:40 GMT
From: "Gregory N. Bond" <[e-mail]>
Subject: Time Machine!?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (David Lai) writes:

       I remember from my youth, I've been thinking of a time machine
   which can go back to the past.  I heard from some other people say that
   scientists are doing researches and that has something to do with, say,
   magnetic fields or magnetic related things.  I'm wondering whether there
   is actually ANY scientists doing research on time machine?  And if so,
   how's the progress?

Try mailing [e-mail].  He will be able to tell you
which Russian scientist has done it.

--
Gregory Bond <[e-mail]> Burdett Buckeridge & Young Ltd Melbourne Australia
   Knox's 386 is slick.            Fox in Sox, on Knox's Box
   Knox's box is very quick.       Plays lots of LSL. He's sick!
(Apologies to John "Iron Bar" Mackin.)

------------------------------

Date: Tue, 30 Mar 1993 15:08:53 GMT
From: Doug Loss <[e-mail]>
Subject: US Satellite Crashing on Brisbane??
Newsgroups: sci.space

In article <1p7tja$[e-mail]> [e-mail] (Dan Corbett) writes:
>The newspapers here in Australia are all abuzz with the news that
>a US satellite is expected to re-enter and to fall somewhere in
>Brisbane, Queensland.  Anybody know anything about this?  Which
>satellite?  Is the prediction accurate?  Has it already happened?
>
>Why do you guys always have to throw your space junk at
>Australia??  ;^)
>

Once is an accident; twice is a coincidence; three times is a tradition.
:-)

Doug Loss

------------------------------

Date: Tue, 30 Mar 1993 10:56:21 CET
From: [e-mail]
Subject: Venus Atmosphere Paper (long)
Newsgroups: sci.space



------------------------------

Date: 30 Mar 93 13:31:27 GMT
From: Goran Olsson <[e-mail]>
Subject: Wanted: Satellite tracking software for unix & VMS
Newsgroups: sci.space

I'm looking for software to display satellite position or ground tracks
from NORAD two-line elements or similar input. The hosts are unix and/or
VMS systems with X-Windows. (We have got programs for MS-DOS and Mac.)

 Companies? Ftp sites?

Suggestions are welcomed. Thanks in advance.

 ==========================================================================
 Goran Olsson                                 Department of Plasma Physics,
 Alfven Laboratory,                    Royal Institute of Technology (KTH),
         [Space Physics Group, Electronics Engineering]
 100 44 Stockholm, SWEDEN                      E-mail: [e-mail]
 ==========================================================================

------------------------------

Date: Tue, 30 Mar 1993 13:45:18 GMT
From: Anthony DeBoer <herboid!adb>
Subject: Why is Venus so bad?
Newsgroups: sci.space,rec.scuba

Frank Crary <[e-mail]> writes:
>The extremely deep dives don't use anything close to a "normal" air
>mixture: Instead of 20% oxygen/80% nitrogen, they use something like
>1% oxygen/99% helium. An inert gas like helium avoids alot of the
>problems of very high pressures (if you don't mind working with
>Mickey Mouse and Donald Duck...)

I've also heard tell of them using "hydrox", a hydrogen-oxygen mixture
with such a low oxygen percentage that allegedly it won't support
combustion.  It still has a high enough partial pressure of oxygen to
support life, at those high pressures.  Apparently, even helium is too
dense for those dives into the four-digit-depths.  There comes a point,
however, when I must admit that anyone diving with this stuff is a braver
man than me.
--
Anthony DeBoer  < [e-mail] | uunet!geac!herboid!adb | [e-mail] >
 NAUI # Z8800, D5482

------------------------------


          id aa01791; 30 Mar 93 2:11:14 EST
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From: Michael Moroney <[e-mail]>
Subject: Re: nuclear waste
Message-Id: <[e-mail]>
Followup-To: sci.environment
Organization: The World Public Access UNIX, Brookline, MA
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[e-mail] (William Reiken) writes:

>In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
>>
>>(1) The total requirement for isotopes for those missions is measured
>>        in kilograms.  While the hazardous-waste output of nuclear power
>>        plants *is* miniscule compared to that from fossil-fuel plants,
>>        it's not *that* miniscule.


>    It has been proposed that by using SDI designed particle accelerators
>that most of the waste could be tranmutated to more useable forms.  Why not
>build a few proccessing plants to do this?

Reprocessing waste is a real taboo.  If it was allowed, it would be
much better to separate out the nasties (transuranics) and feed them back
into a nuke plant, where they get consumed as fuel.  What's left (fission
products) are relatively short-lived and are only a problem for a couple
hundred years (though many will state this is too long)

-Mike

------------------------------

End of Space Digest Volume 16 : Issue 392
------------------------------